Well tool thread lock



May 30, 1950 A. A. BAKER WELL TOOL THREAD LOCK Filed Sept. 29. 1947 F16,F162 v INVENTOR. 4mm 4. Eater W ffi Z J W ATTOE/VFYF Patented May 30,1950 UNITED STATES PATENT OFFICE WELL TOOL THREAD LOCK Aaron A. Baker,Coalinga, (lalifl, assignor to Baker Oil Tools, Inc., Vernon, Calif., acorporation of California Claims.

The present invention pertains to well devices, such as well packerapparatus utilized in the bridging, cementing, acidizing and testing ofwell bores, as well as in other operations.

In the accomplishment of certain purposes in a well bore, severalinterconnected tools, or several interconnected components of a singletool, are run in a well bore on a single running-in string and arecontrolled by manipulating the latter member. It may be desired to firstmove or operate one of the tools or components without moving the otherand then move or operate the latter. As an example, a lower tool may beattached to an upper tool through a left hand threaded connection andthe upper tool may be secured to a tubing string by another left handthreaded connection, or through a J type of pinand-slot look. It isdesired to perform an operation by turning the tubing string andthreading or relatively moving the parts of one of the connectionswithout fear of also threading or relatively moving the otherconnection. Thereafter, one tool is to be disconnected from the othertool by unscrewing the other connection through rotation of the tubularstring.

An object of the invention is to provide an improved lock device for oneof the aforesaid connections, which will insure against relativemovement of its component parts until desired.

Another object of the invention is to provide an improved lock devicefor a threaded connection which precludes inadvertent relative threadingmovement between the component parts of the connection.

This invention has other objects which will become apparent from aconsideration of the embodiment shown in the drawings accompanying andforming part of the present specification. This form will now bedescribed in detail to illustrate the general principles of theinvention, but it is to be understood that such detailed description isnot to be taken in a limited sense, since the scope of the invention isbest defined by the claims appended hereto.

Referring to the drawings:

Fig. 1 is a longitudinal section through a device incorporating thepresent invention, disclosing its parts in one relative position.

Fig. 2 is a view similar to Fig. 1 disclosing the device with the upperconnection partially rotated.

Fig. 3 is a view similar to Fig. 1, with parts of the lower connectionunthreaded from one another.

Fig. 4 is a cross-section taken along the line 4-4 in Fig. .1.

As disclosed in the drawing, the invention has been applied to a wellpacker A and bridging device B, which are interconnected with oneanother and are usually lowered through a string of casing C on thelower end of a suitable tubular string D, such as tubing or drill pipe,to the desired point at which the packer is to be anchored to the casingin packed-off condition. The well packer A may be of any suitableconstruction, the one shown being of the type specifically described inUnited States Letters Patent No. 2,121,051.

Essentially, the packer consists of a tubular body 50 to which the lowerend of the bridging device is secured. The body has a packing sleeve llsurrounding it, whose upper and lower ends are suitably secured,respectively, to upper and lower conical expanders I2, l3 attached tothe body originally by one or more shear screws M. The outer surface ofthe upper expander I2 tapers upwardly and inwardly and is engaged bycorrespondingly tapered upper segmental slips 15 secured to itoriginally in retracted position by shear screws l6. Similarly, theouter surface of the lower expander i3 is tapered inwardly in a downwarddirection and engages correspondingly tapered lower segmental slips llsecured to it originally in retracted position by shear screws it. Theupper end of the body carries an abutment ring l9, and the lower end ofthe body is provided with a lower abutment 20 for engagement with thelower end of the lower segmental slips ll.

A valve housing and guide 2| is secured to the lower end of the body Itand has a back pressure ball 22, preferably buoyant in cement slurry,engageable with its companion valve seat 23 on the body. As described indetail in the above identified patent, the ball valve 22 is held origeinally in ineffective position to one side of the valve housing 2!, butthis element is releasable during the setting operation of the wellpacker in a well casing. Such setting operation occurs as a result ofdropping a trip valve ball (not shown) down through the tubing string Din a known manner, as explained fully in the aforementioned Patent No.2,121,051.

As aforementioned, the bridging ball retaining and releasing device B issuitably secured to the upper end of the well packer. Specifically, thisdevice consists of a bridging ball housing 24 threaded into the upperend of the body It by means of a left hand threaded connection 25, 26.For convenience of manufacture, the housing 24 86 is made in two parts21, 28, its lower sub 21 being attached to the packer body l0 throughthe left hand threaded interconnection 25, 26. The housing is providedwith an enlarged medial chamber 29 in which a bridging ball 3!], orcorresponding valve element, may be confined. The bridging ball, whenreleased, may drop downwardly a comparatively short distance, undergravitational influence, through the lower tubular sub 21 and intoengagement with a valve seat 3! provided in the upper end of the packerbody It].

The bridging ball 38 is held initially against the inner wall of thechamber 25 to one side of the central passage through the apparatus by aretainer sub 32. This sub is threaded into the upper end 28 of thehousing 2 3, preferably through the use of a left hand threadedconnection 33, 34, and has a depending tubular segment 35 integraltherewith adapted to engage the bridging ball 36 and prevent itsdropping downwardly onto the valve seat 3! in the packer body. It is tobe noted that the finger or segment 35 engages the ball and holds it inthe chamber 29, since the distance between the lower end of the segmentand the lower downwardly and inwardly tapered wall 29a of the chamber isless than the diameter of the ball, thereby precluding dropping of thelatter to its bridging position across the packer passageway ltd.

Rotation of the tubing string D, as to the right, causes unthreading ofthe retainer sub 32 from the housing 23 and elevates its segment 35 fromconfining engagement with the bridging ball 33, until the distancebetween the segment and the tapered wall 29a of the chamber is greaterthan the diameter of the ball, which then allows the latter to dropdownwardly through the lower sub 27 and onto the bridging ball valveseat 3 l, closing the central passage lEla of the packer againstdownward flow of fluent substances (see Fig. 2).

The apparatus is made up as disclosed in Fig. 1, with the retainer sub32 threaded downwardly into the bridging ball housing 2 to its fullestextent to confine the bridging ball 33, the housing sub itself beingthreaded into the upper end of the body it of the well packer (see Fig.1). As assurance against unscrewing of the lower sub 21 from the packerPreparatory to upward unthreading of the retainer sub 32 from thehousing 24, the lower sub 21 may be prevented from rotating originallyby a loclr device E eiTecting a connection between the lower sub 2'! andthe body Ill of the well packer A.

The lock device E consists of a shear pin 35 extending substantiallyparallel to the axis of the apparatus into the trip or abutment ring l9attached to the upper end of the packer body. The shear pin 35 extendsinto an outer eccentric member 33 having a circular bore 31 eccentric tothe axis of the apparatus and an inturned flange 38 disposed immediatelyabove an external flange 39 on the lower sub 21. A companion innereccentric member 45 is located within the outer member 36 with its outershoulder M engaging the upper end of the latter. The inner member 4!! issecured to the lower sub 21 by a set screw 42, which need bear butlightly thereagainst.

The inner eccentric member l!) makes a substantially sliding fit withthe lower sub 2?, and also fits within the outer eccentric member 36 insuch fashion as to prevent rotation therebetween, in View of theeccentricity of the two members with respect to the lower sub 2'5. Theinner member 40 actually engages the lower sub frictionally, so that anytendency for the lower sub to rotate also rotates the inner eccentricmember 4!] with it frictionally, such rotation being transferred to theouter eccentric member 36 and through the shear pin 35 and abutment ring19 to the tubular body [ll of the packer A. As assurance that the innereccentric member 2-3 will rotate the lower sub 21, the set screw 52 isprovided, the lower sub carrying the inner eccentric member around withit, and through its eccentric coupling with the outer eccentric member36 transmitting the torque from the lower sub 21 through the shear pin35 to the tubular body Hi.

It is evident from the lock device described that relative rotationbetween the lower sub 2? and tubular packer body [0 cannot occur untilthe shear pin 35 has been disrupted. Suiflcient torque is not applied tothus shear the pin until it is purposely desired to unthread the lowersub 2? from the tubular packer body H1 and remove the tubing string D,bridging ball device B and lock device E to the top of the well bore. 7

The operation of the device will be understood in connection with atypical use of the apparatus. The apparatus is assembled as disclosed inFig. 1, with the ball 30 confined in the chamber 29 by the depending armor segment 35. When in this position, the retainer sub 32 is threadeddownwardly to substantially its fullest extent, spacing an upperexternal flange or shoulder 43 on the retainer sub downwardly withrespect to an inturned flange or shoulder 43 on a stop ring 45 threadedon the housing 24. Leakage between the parts is prevented by theprovisions of suitable side seals 45 on the stop ring 45 and housing 24,which slidably engage the retainer sub 32. The lower sub portion 2i ofthe housing is also fully threadedly connected with the tubular bodyit], and the shear pin 35 of the lock device E is installed in place, aswell as the other eccentric elements 36, 4!] of the lock portion of theapparatus.

The tool is lowered in the well bore and the packer anchored in placewith its slips l5, ll engaging the casing C and the packing sleeve I Iproviding a firm seal between the packer body If! and wall of thecasing. In setting the well packer, the tripping ball (not shown) passesdown through the tubing string D and bridging ball device B around thebridging ball 30, and completely through the apparatus, releasing thebuoyant ball valve 22 from its original ineffective position within thevalve housing 2! (in a known manner), allowing it to move upwardly intoengagement with its companion seat 23.

After anchoring of the casing in packed off conditions, cement slurry orother fluid may be pumped through the tubing string D and apparatus B, Afor discharge from the lower end of the packer. The bleeding ofi ofpressure within the tubing string allows the back pressure ball 22 tomove upwardly and engage its companion seat 23, preventing return orupward flow of fluid through the packer apparatus A.

When it is desired to prevent downward passage of fluent substancesthrough the packer apparatus A, the tubular string D is rotated to theright to unthread the retainer sub 32 in an upward direction from thehousing 24, in view of the left hand threaded connection 33, 34,elevating the attached retainer finger or segmentl35 from engagementwith the bridging ball 30 and allowing the latter to gravitate intoengagement with its companion seat 3! on the upper portion of the packerbody Ill. The bridging ball thus prevents downward passage of fluidthrough the well packer A, and since the back pressure valve member 22prevents upward passage of fluid through the .apparatus, a bridgingpacker is provided which prevents flow of fluids through the apparatusin both directions.

As indicated above, the lock device E is provided to insure againstunthreading of the left hand threaded connection 25, 2% between thelower sub member 27 of the bridging ball housing 24 and the tubular bodyit, insuring that the initial right hand rotation of the tubular stringD will cause unthreading of the retainer sub 32 upwardly with respect tothe bridging valve housing 24, in order to release the bridging ball 30.Any torque incident to such rotation of the tubing string D, imposedupon the bridging ball housing 24, is transmitted through the lockdevice E and its shear pin 35 directly to the tubular body 10, verylittle, if any, of such torque being imposed upon the lower left handthreads 25, 26, thus precluding their inadvertent unscrewing.

Torque imposed upon the lower sub 2! of the housing 24 tends to rotatethe inner eccentric member All with it. Since the inner eccentric membertends to move within the outer eccentric member 36, it is shiftedlaterally into firmer frictional engagement with the lower sub 21, thuslocking the latter and the inner eccentric member Ml securely together.As indicated, the eccentric disposition of the inner member 40 withinthe outer member 35 prevents relative rotation between the two parts,the torque on the lower sub 21 being transmitted through the outereccentric member 36 and through the shear pin 35 and abutment ring illto the tubular body ill, which is prevented from rotating by theanchoring of the slips I5, I! in the casing C. Accordingly, as indicatedabove, the lower left hand threaded connection 25, 26 is substantiallyfree from the imposition of torque, upon the initial rotation of thetubing string D and retainer sub 32 to elevate the latter and releasethe bridging ball 3! for dropping onto the upper valve seat 3!.

After the bridging ball has engaged its seat, the tubing string D may berotated to the right to a further extent, correspondingly rotating theretainer sub 32 and elevating it with respect to the housing 24 untilits external flange 43 abuts the inturned flange or shoulder 44 on thestop ring 45. Such abutting prevents further relative rotation betweenthe sub 32 and housing 2c in a right hand direction. Thereafter, anincrease in the torque imposed upon the tubing string D causes theretainer sub 32 and bridging ball housing 24, including the lower sub 21on the latter, to rotate as a unit, this torque being transmittedthrough the inner and outer eccentric members fill, 36 to the shear pin35. Since the tubular body It and its abutment ring l9 are preventedfrom rotating by the slips I5, ll, an increase in the torque on thetubing string D to a sufficient extent shears the pin 35 and allows thetubing string, retainer sub 32 and bridging ball housing 24 to berotated in a right hand direction to unscrew the lower sub 2] completelyfrom the well packer body l0, permitting withdrawal of the entireapparatus, with the exception of the well packer A, to the top of thewell bore (see Fig. 3). The bridging ball 3d, of course, remains on itsseat 3| to prevent passage of fluid in both directions through the wellpacker A in conjunction with the buoyant back pressure valve ball 22 atthe lower end of the well packer.

It is, accordingly, apparent, that a lock device has been provided whichprecludes disconnection between the upper and lower portions of theapparatus until desired, assuring the proper movement of the upperportion of the apparatus, as in releasing the bridging ball 30 from thechamber, prior to shearing of the pin 35. Although described inconnection with the bridging ball releasing arrangement, it is to beunderstood that the lock device has a general application in-preventinginadvertent disconnection or relative movement between members ingeneral.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In apparatus of the character described, in cluding a pair ofrelatively rotatable members threadedly connected together, separateannular means rotatable with one of said members and removably mountedon said one member, and frangible means connecting said means with said.other member.

2. In apparatus of the character described, including a pair ofrelatively rotatable members connected together, separate annular meansmovable with one of said member and removably mounted on said onemember, and frangible means connecting said means with said othermember.

3. In apparatus of the character described, including a pair ofrelatively movable members threadedly connected together, an innereccentric on one of said members, an outer eccentric on said innereccentric, and frangible means connecting said outer eccentric with saidother member.

4. In apparatus of the character described, including a pair ofrelatively movable members threadedly connected together, a firsteccentric member rotatable with one of said members, a second eccentricmember companion to said first eccentric member and engageabletherewith, and frangible means connecting said second eccentric memberwith said other relatively movable memher.

5. In apparatus of the character described, including a pair ofrelatively movable tubular members threadedly connected together, afirst eccentric member rotatable with one of said members, a secondeccentric member companion to and engageable with said first eccentricmember, and frangible means connecting said second eccentric member:with said other tubular member.

6. In apparatus of the character described, including a pair ofrelatively movable tubular members threadedly connected together, afirst eccentric member rotatable with one of said members, a secondeccentric member companion to and engageable with said first eccentricmember, and releasable means connecting said second eccentric memberwith said other tubular member.

7. Well apparatus, including a well packer having a tubular body, atubular member threadedly connected to said body, a first eccentricrotatable with said member, a second eccentric companion to andengageable with said first eccentric, and frangible means connectingsaid second eccentric with said tubular body.

8. Well apparatus, including a well packer having a tubular body, atubular member threadedly connected to said body, an inner eccentricfrictionally engageable with said member, a companion outer eccentricencompassing said inner eccentric, and frangible means connecting saidouter eccentric with said body.

r 9. Well apparatus, including a well packer having a tubular body, atubular member threadedly connected to said body, an inner eccentricfrictionally engageable with said member, a set screw threaded in saidinner eccentric and engaging said tubular member, a companion outereccentric encompassing said inner eccentric, and frangible meansconnecting said outer eccentric with said body.

10. In apparatus of the character described, an 10 Number outer tubularmember, an inner tubular member threadedly and detachably connected tosaid outer member, a first eccentric member rotatable with said innermember, a second eccentric member companion to and engageable with saidfirst eccentric member, and releasable means connecting said secondeccentric member with said outer tubular member.

AARON A. BAKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date 1,243,364 Walker Oct. 16, 1917 FOREIGNPATENTS Number Country Date 28,929 Great Britain Dec. 16, 1912

